Leads implanted in or about the heart have been used to reverse certain life threatening arrhythmia, or to stimulate contraction of the heart. Electrical energy is applied to the heart via an electrode to return the heart to normal rhythm. Leads are usually positioned in the ventricle or in the atrium through a subclavian vein, and the lead terminal pins are attached to a pacemaker which is implanted subcutaneously.
For example, one approach is to place the electrode against the ventricular septum above the apex. However, current leads require a lead placed with the electrode against the septum above the apex to be actively fixated. This may possibly result in trauma to the heart from cyclical heart motion, and lead to micro-dislodgement of the electrode, and relatively higher defibrillating and pacing thresholds. Moreover, other factors which can be improved include better electrode contact, and easier implanting and explanting of the leads.